Catastrophe ends on a note pitched perfectly between optimism and disaster

The final scene of the final episode of the final season of Catastrophe (ABC, Thursdays at 9.45pm) is, like most of what precedes it - perfectly judged. Depending on your perspective, it’s either an image of cautious optimism or one of impending disaster – the catastrophe, if you will, long promised by the title. I won’t give it away but rest assured, once you’ve seen it you won’t forget it.

That this most excellent show should close on such a glass-half-empty/glass-half-full note is apposite. The marriage at the heart of the show – born from an accidental pregnancy born from a week-long fling born from a one-night stand – has always looked either refreshingly unconventional or doomed to collapse, depending on the tilt of the head and whose head is doing the tilting.

No matter that it’s a comedy (albeit one with frequent visits to the dark side), Catastrophe is probably the most honest and insightful show ever made about the work involved in keeping a relationship on the rails and the need to try to see it through the other person’s eyes, at least occasionally.

Rob is a recovering alcoholic, whose erstwhile recovery went off the rails completely at the end of season three. This season opens with him in a neck brace, in a courtroom, and in a state of suspended licence; had he not told the magistrate he was distressed when he crashed his car into a bus because he’d just discovered his wife had given some light hand relief to a university student, it could have been so much worse.

Sharon Horgan and Rob Delaney in Catastrophe.Credit:ABC

Sharon, of course, is none too pleased about being thrown under the bus like this. Nor is she convinced Rob can be trusted to stay on the road to sobriety. She’s using the find-my-phone widget to find her husband and to grill him when he gets home about which pubs he passed, and which ones he didn’t.

Catastrophe is probably the most honest and insightful show ever made about the work involved in keeping a relationship on the rails.

She’s furious too that he gets to hang out with the old ladies in the charity shop on weekends as part of his community-service punishment while she has to spend endless hours in the park with the kids. See: glass-half-whatever, right?

The plot lines this season include Sharon getting a new principal, who may or may not be a sleazebag; Rob getting a new boss (played by Sex and the City’s Mr Big, Chris Noth), who most certainly is a sleazebag; friends Fran (Ashley Jensen) and Chris (Mark Bonnar) dealing with their separation; and the death of Rob’s mother, Mia.

This last was perhaps unavoidable. Mia was played by Carrie Fisher, who suffered a heart attack while flying home to the US after filming the final episode of season three of Catastrophe in the UK. It doesn’t quite rate alongside the “how will they deal with Leia in Episode IX” dilemma facing Star Wars’ producers, but resolving the Mia storyline was always likely to be a priority for a show that has never avoided the tough topics.

Rob’s palpable anger and grief at his mother’s death, and at the arrival of his alcoholic, wife-beating father at the funeral, is shockingly believable. So too is the fact he turns it on Sharon.

What makes this season all the more remarkable is that Delaney was writing it soon after the death of his two-year-old son who died of brain cancer. Going to work, he has said, was important not just for his own sanity, but for his wife and their other kids. It proved life could still go on.

It’s that willingness and ability to tap into the deep wells of experience, good and bad, that makes Catastrophe such an absolute gem.

See it and weep. Whether it’s with laughter or with sadness will probably come down to which way you’re tilting your head at the time.